Power-driven mechanism for operating escapement and other instrumentalities of typewriters or like machines



OPERATING ESCAPEMENT AND Patented Aug. 7, 1951 UNITED STATES PATENT OFFICE POWER-DRIVEN MECHANISM FOR OPERAT- ING ESCAPEMENT AND OTHER INSTRU- MENTALITIES OF TYPEWRITERS OR LIKE MACHINES Application June 13, 1949, Serial No. 98,738

9 Claims; 1

This invention relates to power driven mechanism for operating escapement and other instrumentalities of typewriter or like machines.

In one of its aspectsthe invention-relatesmore particularly to improvements in power generating or transmitting mechanism of the kind disclosed in the .co-pending application of William H. Kupper, Serial No. 6,066, filed February 3, 1948. The mechanism disclosed in this co-pending application includes a driving member in the form of a continuously rotating snatch roll adapted to transmit drive to a typewriter instrumentalityi Another object of the invention isY to provide'Y adjusting or drive-eifort-varyingmeans of the kind referred to by which ther adjustment is effected by variably limiting the extent' to which the toothed driven element islnioved into a toothinterspace on the snatchroll.

In another of itsfaspects, the invention relates more particularly to mechanism or connections;

for transmitting operating eiiort tothe escapement mechanism ofa typewriter or likemachine'.

Another object of` theV invention is'to providea new and improved train of'driving connections between a power generating mechanismandthe" escapement mechanism ora typewriter'or like` machine, the connections including cushioningmeans oi novel construction adapted to minimize" abruptness of operation'o thelescapementmechanism, avoid jamming of the parts5`and minimize noise and vibration.

A further object of the invention isto provide an escapement mechanism and associated" train of power transmitting connections which areso" coordinated as toenable the escapem-ent meeha- Y nism to be adjusted closely for edi-cient operation without its being necessary to'make compensating adjustments in the power drivingrmechanism' or in the intervening-train of driving connections'.

Other objects ofthe invention will become Vapf parent froml a reading ofthe following description of a preferredfembodiment ofthe'invention;` the appended claims,` andv the accompanying;

drawing, in which:

lFigure -l is a view, partly-'in eievationandpart:

ly in vertical section, fore and ait of a typewriter embodying the invention, showing only some f theV conventional or standardV typewriter parts in order to illustrate the application of mechanism embodying the invention t'o a typewriter construction; l

Figure 2 is a vertical,l sectional view on the line 2;-2- of Figure l, drawn on an enlarged# scale and showing escapement mechanism and actuating mechanism therefor constructed in accordance with the invention;

Figure 3ds a horizontal section on the irregular line 3-3 otFigu'i-ez; and

Figure 4 is a detail, perspective View of an escapementoperating-lever'.

The invention may be embodied in typewriters or likemachines--of various kinds. For the purposes or illustration, the invention is shown as being embodiedi in an cnice type typewriter having, exceptfor the power mechanism Yto be describ'ed many features in common with the well known RoyalI standard' typewriter, The drawings show only enough of the standard-or known typewriter construction to assist in illustrating th-e manner `in which' mechanism embodying the invention may be' ooordinatedwith other parts of a typewriter construction. Y

The knownconstruction' illustrated includes a mainframe A on which a carriage is mounted for letter' spacing and return movements by For controlling the feeding of` thecarriage inf letter-spacingdirectionv to take place by letter space increments; theA carriage` is equipped' with alraf'ck 4 (Figure 1), cooperalilef with an escapement mechanismgenerally designated BL With exceptions to4 be pointed out hereinafter', the escap'ement `mechanism and the esca'pcm'ent opferating mechanism are similar to mechanisms customarily-embodied in Royal standard or manually operated typewriters, and include an escapementpinion: coupled by a ratohetpawl (not showm' with'A an escapementlwheel S'journa'ledon" a pin 1 carriedby a frame-mounted bracket `8. The bracket'Sj'is equipped with coneshaped bearing screws; .9i-9 extending-f into conl formingly shaped'bearinfg.: recesses in mounting f earsj 0"-`-IU"integral with an oscillatable escapement rocker plate I I. Rocking of the plate part II in one direction on the screws 9-9 is limited by a stop finger I2 secured to the bracket 9 by screws I3. The linger I2 extends from behind the plate II forwardly past the plate, is then turned so as to extend parallel to and in front of the plate, and has its extreme end part I2a projected rearwardly so as to be engageable by a part of the plate above the pivots 9-9 when the plate is rockedcounterclockwise as viewed in Figure 1. Rocking of the plate in the opposite direction is limited by a stop linger I4 secured to the bracket 8 by screws I5, and having a part IIIa projecting forwardly through an opening I6 in the bracket 8 so as to be engageable with the rear face of the rocker plate II when the latter is rocked clockwise as viewed in Figure 1. i Either or both of the fingers I2 and I4 can be bent,

mauled, or otherwise deformed so as to adjust the limits of rocking `of the plate I I.

The plate II is equipped with the usual fixe dog I'i and limber dog I8 pivoted on the plate as at I9, and urged counterclockwise as viewed in Figure 2 by a spring 20 interposed between a heel 2l on the limber dog and an ear 22 on the rocker plate II. An abutment screw 23 has threaded connection with a boss or lug 2li on the back of the plate II, and can be adjusted for determining the limit of rocking of the limber dog I8 when Ythe latter is engaged by a tooth ofthe escapement wheel 6. A normalizing or return spring 25 is interposed between a part of the rocker plate I I above the pivots 9 and a subbracket 26 mounted underneath the framernounted bracket 9 by a screw 2'I, the spring 25 normally holding the rocker plate II in its Figure 1 position with the limber dog I3 holding the escapement wheel 6 against rotation and hence, holding the carriage stationary. When the rocker plate II is oscillated back and forth, the dogs Il and I8 will cooperate with the escapement wheel in a well known manner for effecting the desired letter-spacing incremental movements of the carriage.

In general, the parts described so far do not, in themselves, constitute the present invention. The invention resides in other parts to be described, and combinations of such other parts with each other and with parts already described.

Broadly considered, oscillation of the plate II and letter-space feeding of the carriage are effected by power driven means generallydesignated C which are made effective lby operatorcontrolled means D including a manually operable space bar element 28. Power is transmitted from the power-driven means C through a train of driving connections E extending from` the means C to the escapement mechanism B. The construction and arrangement of the parts is such that, upon depression of the space bar 28, a quickly generated power impulse is transmitted through a cushion device to the plate II to rock the'latter clockwise as viewed in Figure l, the power impulse being of short duration and being followed by returning of the plate Il to its lever onk a xed frame cross bar 34.

tweenthe continuously moving driving member and the train of connections E. The driver is constituted by a continuously rotating element, more particularly a toothed snatch roll or bar 29, which may be of known form, and which is adapted to be driven in the direction of the arrow a in Figure 1 by any suitable means, but preferably by an electric motor (not shown).

The means for transmitting drive from the driver 29 to the connections E includes an actuator 39 which extends fore and aft of the typewriter and above the member 29. The actuator 39 is pivoted as at 3| to a lever 32 at a point olfset relatively to the pivotal mounting 33 of the The actuator has a forwardly extending part 35 projecting under anabutment or guide plate 36 mounted by screws Sion the frame A, to extend parallel to the'snatch roll 29. A spring 38, interposed between the front end of the actuator 3U and an anchor plate 39, yieldably urges the actuator to rock clockwise, and thus normally maintains the actuator in the position shown in Figure 1 with its front end part 35 lbearing against the abutment or guide plate 36. Another abutment 49 is disposed below the abutment 36, and is slotted to receive and guide the lower extremity of the actuator part 35 for sliding movements.

In order to apply a power impulse to the train of driving connections E, the actuator 39 is operatively but indirectly connected to the driving member 29, the actuator itself never engaging the driving member. Mechanism for bringing about the operative connection of the actuator element 39 to the member 29 includes an inter-A ponent pawl 49', pivoted as at 4I on the actua-.

tor. A spring 42, anchored to the actuator 39 and connected to the pawl 49', biases or urges.; the latter to rock clockwise so as to move its nose 49a into engagement with the snatch roll` i 29. Normally, the pawl is maintained out of en. gagement with the snatch roll by the restraining action of a control element or trigger 43 which is pivoted as at 43e on the actuator 39. In thenormal position of the trigger, its rear end 44. engages a holding surface 45 on the pawl so as,` j to prevent the spring l2 from rocking the pawl;- element 46 into drive-transmitting engagement. The pawl 46' is.

with the driving member 29. formed with an inclined resetter cam face 45. which is located just below the holding surface,- 45, and which is acted upon by the trigger for rocking the pawl counterclockwise, and thus resetting it in normal, inoperative position.

-Operator controlled means is provided for bringing about operative driving connection between the driver29 and the actuator 39. This means includes the manually operable space bai` element 26 pivoted as at 91 on the frame A. The space bar 28 is carried by a composite lever construction including right and left hand arms 28a f and 28b respectively, joined by a cross rod 28C.

Normally, the space bar assembly is held in its upper position with the arms 28a and 28lo engaging a cushion stop 4B.

The space bar arm 28aL has an upward projection I9 disposed behind an arm 5I) of an operating lever 5l, pivoted as at 52 on a frame-mounted cross bar 53. The lever 5I has another arm 54 on which a limber dog or flipper 55 is pivoted at 56. A spring 51 urges the limber dog 55 to rock clockwise( to yieldably retain it in its normal position of rest against a limit stop 58. The dog 55 can swing counterclockwise from the position shown in Figure 1, but cannot move clockwise from this position. Areturning spring 59, inter-- posed between the space bar arm 28a and a short arm 60 on the lever 5|, yieldably holds the lever 5I and the space bar arm 28a in their normal positions. In the normal positions of the parts, the lower end of the limber dog 55 overlies a contact ear 6| on the actuator 3D1.

In operation, when the space bar 28 is depressed, thelever 5I is rocked clockwise to cause the ipper 55 to push the actuator 36 downwardly to an initial extent suflicient to bring the trigger 43 into engagement with the abutment 46. This i causes the trigger to be rocked clockwise about its pivot 43a, so as to release the pawl 4D', which is then moved by the spring 42 into engagement with the snatch roll 29. The snatch roll then drives the pawl 46 and actuator 3Q as a unit so as to rock the lever 32 and operate the escapement mechanism through the train of connections When the pawl 40 is cast oiic from engagement with the snatch roll 29, the spring 38 lifts the actuator 3G to bring the trigger 43 into engagement with the upper, trigger-resetting abutment 36. This causes the trigger 43 to be rocked counterclockwise, so as to move its end 44 against the resetting cam face 46 of the pawl 4a', thereby restoring the latter to its inactive position. The parts of the mechanism C will then be returned to their normal positions by a spring 62 interposed between a rearwardly extending arm 32a on the lever 32 and the lower .part of a bracket 63 fixed to the frame cross bar 34. The escapement normalizing spring 25 eooperates with the spring 62 for returning the parts to their normal positions. The lever 32 is pron vided with a downwardly extending projection 64 engageable with the upper part of the bracket 63 for limiting the return movement oi the lever 32 and the connected parts to their normal positions under the urge of the springs 62 and 23.

Means are provided for adjusting or varying the amount of driving impulse generated by the power mechanism C. In accordance with the invention, this variation or adjustment is eiected by variably limiting the extent to which the actuator pawlnose 46a enters a tooth interspace on the snatch roll 29 under the urge of the spring 42 when the restraint of the trigger 43 on the pawl 40 is discontinued. In the form shown, the actuator 30 is provided with a downwardly extending stop element or nger 65 which is disposed` in front of and normally out of contact with a downwardly extending stop part, heel, or ringer 66 on the pawl 40'. When'the pawl 4t" is rocked clockwise by the spring 42 so as to'move the pawl nose 46a into a snatch roll tooth interspace, the pawl stop 66 moves toward the actuator stop 65, which may be so positioned as to be engaged by the stop 66 to arrest rocking of the pawl 4D before the tooth 4Ua moves to the root of the snatch Aroll tooth interspace. By variably positioning one of the vstops E5, 66, e. g., by bending the stop 65 towards or away from the stop 66, the extent to whichA the pawl tooth 40a enters the tooth interspace Vcan be varied. Consequently, the angle through which the snatch roll rotates while in contact with the pawl, which determines the amount of driving of the pawl 4U and actuator 3|] by the 'snatch roll 29, can be varied. Any suitable means or construcion may be provided ior adjusting one of the stops 65, 66 relatively to the other, but in the preferred construction the stop '65 is 'formed integrally withV the actuator 3U so 'as to be bendable toward or away from the stop 66.

It is apparent that power mechanisms including such parts as the snatch roll 29, actuator .30 and pawl 40 for operating instrumentalities other than escapement mechanism, e. g., type actions, carriage return mechanisms and so on, may be provided with means corresponding to the relatively adjustable stops 65 and 66 for varying the extent to which a pawl nose enters a snatch roll tooth interspace, so as to vary the power delivered to the operated instrumentality.

In typewriters or like machines in which all or some of the instrumentalities to be operated, e. g., type bars, carriage return mechanism, tabulating mechanism, as well as escapement mechanism, are operated by power, it may be desirable to provide means for varying collectively the extent of driving of the several actuator pawls corresponding to the pawl 40 and associated with the other mechanisms referred to. This may be accomplished by providing a knock off bar 61 mounted on the `main frame so as to extend under the front ends of all of the actuators corresponding to the actuator 36 .shown in Figure 1. Any suitable means (not shown) may be provided for adjustably tilting or otherwise variably positioning the knock oir bar 61 so that it will be 'engaged by the lower ends of the actuators to control the timing of disengagement of the associated actuator pawls from the snatch roll.

The train of connections E is so arranged, constructed, and coordinated with the power mechanism C and escapement mechanism B as to suppress or cushion the impact or concussion whichnotherwise would be transmitted abruptly from the power mechanism C to the escapement mechanism B. Accordingly, undesirable noise and harmful shocks are prevented, and danger of jamming of the machine with resultant damage is eliminated. In the construction shown, a pull link 68 is pivoted as at 69 to the lever 32, and is pivoted as at 'I0 to a lever 1|. The lever 'Il is pivoted at 'l2 on the lower arm 'I3 of a lever 'I4 provided with pins or trunnions 't5-l5 by which it is pivoted on a bracket 16 mounted on the main escapement mechanism bracket "8. The

upper end of the lever 'i4 has an arm VI formed with a rounded end 'I8 disposed immediately in front of the escapement rocker plate l l above the pivots -99.

The arm 13 of the lever 14 has a rearwardly ofi-set ear 19 to which is anchored the rear end of a force-transmitting cushion spring 8l), the front end of which is connected in a hole 8l in the lever 7|. The spring 8l) urges the lever 1l relatively counterclockwise with respect to the lever 'I4 as viewed in Figure 3, such move= ment of the lever 1I being limited by engagement of `an ear 82 formed integrally on the lever 'Il with the lower arm 'i3 of the lever I4. In the normal Vposition of the parts, shown in Figure 3, the stop ear 82 is in contact with the lever arm 13, andthe spring is preloaded or `under initial tension.

In operation, when the space bar 2B is depressed, the pawl 40 is moved into engagement with the snatch roll 29, the actuator 30 is moved forwardly, and the lever 32 is rocked counterclockwise as viewed in Figure 1, in the manner previously explained. A momentary, quickly accelerating impulse is transmitted through the pull` link 68 to the lever 1I to rock the latter clockwise as viewed in Figure 3. Such rocking ofthe lever `H does not transmit a positive actuating effort tothe lever 14 and escapement rocker 'plate Il, but acts through the cushion spring 80 to rock the lever i4 mpositively or yield- .it engages the stop finger |48.

ingly, but withV sufcient force to enable the lever 'I4 to'rock the escapement plate IlY until The driving impulse is of short or momentary duration, and, as soon as the pawl 40 becomes disengaged from the snatch roll, the springs 25 and 62 return the actuator 30, lever 32, link 68, levers'll and 14, and escapement plate Il to their normal positions limited or determined by the stop fmger 12a. The stop Ila and/or the stop Illa-may be adjusted to provide a very fine adjustment of the limits of oscillation of the plateY Il for effecting most emcient operationof the escapement mechanism. Inasmuch as the escapement rocker plate H is operated in bothdirections by springs, in one direction by the spring 80 and in the other direction by the spring 25, it is not necessary to make compensating adjustments of the parts of the mechanism C when the stops l2a and Ida are adjusted. The spring 80 has suiiicient capacity to yield to enable the operating force provided by the mechanism C to operate the escapement plate ll eiectively without its being necessary to coordinatev exactly the adjustment of the stop finger HI?L and the stops 65 and SS on the actuator 30 and pawl 40.

The mechanism disclosed embodies the invention in a preferred form, but it is intended that the disclosure be illustrative rather than dennitive, the invention being defined inthe claims.

I claim:

1. In power operating mechanism-for a typewriter or like machine, a carriage escapement mechanism; a driving member; an actuator; means including a cushioned motion-transmitting connection interposed between said actuator and said escapement mechanism; an interponent mounted on said actuator for movements into and out of operative engagement with said driving member and being biased to move into en'- gagement therewith; a trigger normally maintaining said interponent disengaged from said driving member; a manually operable escapement control element; means responsive to depression of said element foractuating said trigger to release said interponent and enable it to move into engagement with said driving member, whereby said actuator will be driven by said driving member so as to operate said escapement mechanism; and trigger re-setting means effective upon return movement of said element when said driving member is stationary for moving said trigger reversely to its releasing movement and thereby disengaging said interponent from said driving member.

2. In a power operating mechanism for a typewriter or like machine; a carriage escapement mechanism; a rotatable driving member; a movably mounted actuator; means including a cushioned motion-transmitting connection interposed etween said actuator and said escapement mechanism; an interponent mounted movably on said actuator; a spring urging said interponent to move into drive-transmitting engagement with said driving member; a trigger mounted movably said spring into drive-transmitting engagement with said driving member, whereby said actuator will be driven by said driving member so as to operate said escapement mechanism.

3. In a power operated typewriter or like machine, a carriage escapement mechanism including an oscillatable part; a driving member; a train of connections between said driving member and said oscillatable part including an actuator drivable by said driving member, a first piv-V oted lever adapted to operate said oscillatable part, a second lever, means pivotally mounting said second lever on said rst lever, a spring interposed between said levers and urging said secondY lever to rock in one direction about its pivot on said first lever, a stop on one of said levers engageable with the other of said levers for limiting rocking of said second lever in said direction, and means connecting said second lever to said actuator and being operable by said actuator to rock said second lever in the opposite direction whereby to rock said rst lever through said spring; and manually operable means for controlling transmission of drive from said driving member to said actuator.

4. In a power operated typewriter or like machine, a carriage escapement mechanism including an oscillatable part; a continuously driven rotary toothed snatch roll; a train of connections between said snatch roll and said oscillatable part including an actuator normally disconnected from said snatch roll but being controllably connectible therewith substantially i11- stantaneously, whereupon the actuator is abruptly accelerated from restposition, a rst pivoted lever adapted to operate said oscillatable part, a second lever, means pivotally mounting said second lever on said rst lever, a spring interposed between said levers and urging said second lever to rock in one direction about its pivot on said first lever, a stop on one of said levers engageable with the other of said levers for limiting rocking of said second lever in said direction. and means connecting said second lever to said actuator and being operable by said actuator to rock said second lever in the opposite direction whereby to rock said rst lever through said spring; and manually operable means for controlling connecting of said actuator to said snatch roll.

5. In a power operating mechanism for a typewriter or like machine, a rotatable toothed snatch roll; an instrumentality to be operated by said snatch roll; means for transmitting drive' from said snatch roll to said instrumentality including an interponent having a contact part normally disengaged from said snatch roll but being engageableV therewith by entrance into a toothV interspace thereof; operator controlled means for effecting such engagement of said interponent part with said snatch roll; an adjustable stop separate from said operator controlled means Yand said snatch roll; and another part on said interponent engageable with said stop for variably limiting the extent of entrance of said interponent contact part into a snatch roll tooth interspace, adjustment of said stop thereby variably Adetermining the extent of driving of said interponent and said instrumentality by said snatch roll.

6. In a power operating mechanism for a typewriter or like machine, a rotatable toothed snatch roll; an escapement operating mechanism to be operated by said snatch roll; means for transmitting drive from said snatch roll to said escapement operating mechanism including an interponent having a contact part normally disengaged from said snatch roll but being engageable therewith by entrance into a tooth inter space thereof; operator controlled means for effecting such engagement of said interponent part with said snatch roll; an adjustable stop separate from said operator controlled means and said snatch roll; and another part on said interponent engageable with said stop for variably limiting the extent of entrance of said inter-- ponent contact part into a snatch roll tooth interspace, adjustment of said stop thereby variably determining the extent of driving of said interponent and said escapement operating mechanism by said snatch roll.

7. In a power operating mechanism for a typewriter or like machine, a rotatable toothed snatch roll; an instrumentality to be operated by said snatch roll; an actuator connected to said instrumentality and being normally disconnected from said snatch roll; a spring urged interponent movably mounted on said actuator and having a contact part normally disengaged from said snatch roll but being engageable therewith under spring urge by entrance into a tooth interspace thereof; operator controlled means normally restraining said interponent from engagement with said snatch roll but being operable for discontinuing its restraint to enable the spring urge to effect engagement of said interponent contact part with said snatch roll; an adjustable stop on said actuator; and another part on said interponent engageable with said stop for variably limiting spring-urged movement of said interponent relatively to said actuator, adjustment of said stop variably determining the extent to which said interponent contact part can be moved by spring urge into a snatch roll tooth interspace, and consequently variably determining the extent of driving of said interponent, said actuator, and said instrumentality by said snatch roll.

8. In a power operating mechanism for a typewriter or like machine, a rotatable toothed snatch roll; an escapement operating mechanism to be operated by said snatch roll; an actuator connected to said escapement operating mechanism and being normally disconnected from said snatch roll; a spring urged interponent movably mounted on said actuator and having a contact part normally disengaged from said snatch roll but being engageable therewith under spring urge\by entrance into a tooth interspace thereof; operator controlled means normally restraining said interponent from engagement with said snatch roll but being operable for discontinuing its restraint to enable the spring urge to effect engagement of said interponent contact part with said snatch roll; an adjustable stop on said actuator; and another part on said interponent engageable with said stop for variably limiting spring-urged movement of said interponent relatively to said actuator, adjustment of said stop variably determining the extent to which said interponent contact part can be moved by spring urge into a snatch roll tooth interspace, and consequently variably determining the extent of driving of said interponent, said actuator, and said escapement operating mechanism by said snatch roll.

9. In a power operating mechanism for a typewriter or like machine, a rotatable toothed snatch roll; an instrumentality to be operated by said snatch roll; an actuator connected to said instrumentality and being normally disconnected from said snatch roll; a spring urged interponent movably mounted on said actuator and having a contact part normally disengaged from said snatch roll but being engageable therewith under spring urge by entrance into a tooth interspace thereof; operator controlled means normally restraining said interponent from engagement with said snatch roll, but being operable for discontinuing its restraint to enable the spring urge to effect engagement of said interponent contact part with said snatch roll; a first stop element on said actuator; and a second stop element on said interponent engageable with said rst stop element for limiting spring-urged movement of said interponent relatively to said actuator and thus limiting the extent of entrance of said interponent contact part into a snatch roll tooth interspace and determining the extent of driving of said interponent, said actuator, and said instrumentality by said snatch roll, one of said stop elements being bendable towards and away from the other of said stop elements for varying the limit of entrance of said interponent contact part into a snatch roll tooth interspace.

HENRY J. CHART.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 897,269 Brooks Sept. 1, 1908 1,614,475 Hokanson Jan. 18, 1927 1,712,514 Nepper May 14, 1929 1,737,439 Stickney Nov. 26, 1929 1,900,690 Benzing Mar. 7, 1933 2,008,384 Benzing July 16, 1935 

